CVE-2005-1021
HighSummary
A memory leak in Secure Shell (SSH) in Cisco IOS versions 12.0 through 12.3, when authenticating against a TACACS+ server, allows remote attackers to cause a denial of service (memory consumption) via an incorrect username or password.
Risk Assessment
The risk is that a remote attacker can cause a network device to crash due to memory exhaustion, potentially disrupting network operations and service availability.
Recommendation
It is recommended to upgrade Cisco IOS to a version later than 12.3, which includes a fix for the memory leak. If an upgrade is not possible, consider restricting SSH access or using alternative authentication methods.
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Original NVD description (English source)
Memory leak in Secure Shell (SSH) in Cisco IOS 12.0 through 12.3, when authenticating against a TACACS+ server, allows remote attackers to cause a denial of service (memory consumption) via an incorrect username or password.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS